historic streetcars on the city's main artery will disappear. the buses shifting onto mission street one block over commuters may or may not have noticed the alert at bus shelters, warning ever route changes, because of so-called super bowl festivities. >> i didn't know that. all because of 49ers, right? okay. >> reporter: does that make sense? >> kind of, yes. >> reporter: for muni, the precautions make sense because of mayhem after the world series months ago. they bashed in a bus before set it on fire. muni does not want to get burned again. >> vehicle was destroyed. it's about a $700,000 bus which had just gone through a rehab, bringing the pricetag up to l1 million. >> reporter: tomorrow night electric buses will be gas powered rigs. to keep cable cars out of harm's way, those on powell and california streets will go to the barn, replaced by buses. >> tourists ride the cable car and love the cable car. >> reporter: it doesn't sit well with everyone. >> i know they are talking the buses and i understand that, but to take the cable cars, it's